The invention relates to a traffic information apparatus, comprising a vocabulary memory in which each vocabulary element can be addressed by means of a code number designating a vocabulary element, the memory containing, for each vocabulary element, digital data describing the relevant vocabulary element, and also comprising a speech synthesizer for generating the phonemes corresponding to the representation of said vocabulary elements in the form of speech.
An apparatus of this kind is, for example a car radio receiver, intended to receive and utilize so-called RDSITMC signals, or a road guidance apparatus which is also referred to as a navigation apparatus. It is capable of supplying traffic information messages, or messages for guiding a vehicle, by displaying the messages on a screen and/or by outputting the messages by speech synthesis.
A speech synthesizer is known from the document EP-A-0 059 880. According to this document, the definition of a word is given in the form of ASCII characters which are sequentially entered and a microcontroller interrogates a ROM memory containing pronunciation rules in order to establish how a given set of characters is to be pronounced. A problem is encountered in that in given languages several different pronunciation rules are applicable, depending on the words. For example, in English the characters "gh" in "rough" and "ghost" are not pronounced in the same way. In order to solve this problem, the speech synthesizer in the cited document utilizes a complex set of rules which must take into account a large number of different situations and which differs for different languages (English, German, French, etc.).
It is an object of the invention to simplify the generation of phonemes and to reduce the required memory.